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Blood Test Tracker

RBC Folate by age and sex

What’s typical for RBC folate at every adult age, from a U.S. government health survey of 16,487 people, next to the usual ranges labs print.

NHANES 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 202316,487 adultsAI-drafted. Awaiting verification

What’s typical at one age

Pick a sex and an age to see the spread among U.S. adults like that, and type a result to see where it falls.

U.S. women aged 40–49

1,561 people in NHANES, 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 2023.

Women aged 40–49, 1,561 people: median 481, middle half 379 to 621, middle 90% 257 to 940 ng/mL. Usual range 280 to above.

Median (half are lower)
481 ng/mL
Middle half of people
379 to 621
Middle 90% of people
257 to 940
Usual range a lab prints
280 to above

Shaded: the middle 90% and middle half of people. Dark line: the median. The bracket above: the usual range.

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Across adult life

NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.

How RBC Folate varies with age in the U.S.Shaded: middle 90% and middle 50% of people. Line: the median. ng/mL. Point at any age, or focus the chart and use the arrow keys, to read both sexes in words.

Use the left and right arrow keys to read each age. Shift moves five years.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Every percentile

Download this table (CSV)

The 25th percentile means a quarter of people in that group had a lower result. In ng/mL. A dash means too few people were measured for the survey to publish that number.

Women

RBC Folate percentiles for U.S. women by age, in ng/mL, NHANES 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 2023
AgePeople2.5th5th10th25thMedian75th90th95th97.5th
18–291,733217243275339419521646746839
30–391,5442162562943614645967588731,070
40–491,5612192572983794816217849401,060
50–591,2822292723203955126718359901,176
60–691,6022352843314085217209701,1301,349
70–799252392843254285897991,0401,1701,372
80+4682833163634686539241,2011,3601,642
All adults9,1152252603033804906588651,0401,190

Men

RBC Folate percentiles for U.S. men by age, in ng/mL, NHANES 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 2023
AgePeople2.5th5th10th25thMedian75th90th95th97.5th
18–291,310213242280342420508609693794
30–391,038218242297381472570670759918
40–491,022226260298372472587728831932
50–591,1472232573083995036317959671,097
60–691,4832472793234115307029271,1401,260
70–799232552863314275928041,0301,1811,343
80+4492592913484465968361,0941,2901,392
All adults7,3722222583023794816147959621,140

About these numbers

  • NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.
  • Assays differ between labs and between NHANES cycles. Values from a commercial lab can sit a few percent higher or lower than NHANES for the same blood. Earlier cycles were bridged to the 2021-2023 method with NCHS equations where NCHS recommends it.
  • Age 80 and over is top-coded at 80 in public NHANES files, so the 80+ cell mixes everyone 80 and older.
  • 2021-2023 (cycle L) had a 25.7% exam response rate and no race/income oversampling; NCHS advises caution when combining it with earlier cycles.
  • Red blood cell folate by microbiologic assay.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Data. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. https://wwwn.cdc.gov/nchs/nhanes/

How we use survey data

The usual adult range

Labs print one adult range for RBC folate, whatever your age.

  • Adults280 and above ng/mL

Every range and its source